In a saucepan over medium heat, simmer cherries, 1 cup sugar, 1 cup water, and 1 tablespoon lemon juice. Once cherries are broken down and liquid is syrup-like, remove from heat. This is about 30 minutes.
Strain cherry syrup and discard skins.
Make lemonade by adding lemon juice, sugar, and cold water. Stir well.
Pour cherry syrup into the bottom of each glass (about 1/4 cup) and finish with lemonade.
Garnish with maraschino cherries and lemon slices.
You can also mix the cherry syrup with the lemonade in a pitcher instead of serving layered-style.